Floor cleaner

ABSTRACT

A floor cleaner including a fluid flow path extending from a dirty air inlet to a clean air outlet, a fluid flow motor, a separator housing, and a cylindrical filter chamber containing a cylindrical filter media. The filter chamber includes a filter inlet that enters the filter chamber tangentially. The filter inlet has a longitudinal height that is a substantial portion of the height of the filter chamber and the filter media.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application No. 62/937,952, filed Nov. 20, 2019, the entire contents of which are hereby incorporated by reference herein.

BACKGROUND

The present invention relates to floor cleaners.

SUMMARY

In one embodiment a floor cleaner is disclosed, the floor cleaner including a fluid flow path extending from a dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, a separator housing, and a cylindrical filter chamber housing a cylindrical filter media. The separator housing includes a separator air inlet in communication with the dirty air inlet and a separator air outlet. The cylindrical filter chamber includes a first end, a second end, and a cylindrical sidewall extending between the first and second ends in a longitudinal direction. The cylindrical filter chamber includes a filter inlet tangential to the cylindrical sidewall and in fluid communication with the separator air outlet. The cylindrical filter media is positioned in the filter chamber. The cylindrical filter media includes an upstream portion and a downstream portion. The upstream portion is spaced from the cylindrical sidewall between the first end and the second end. The downstream portion forms a portion of the fluid flow path upstream of the fluid flow motor. A longitudinal height of the filter inlet is at least 60% of a longitudinal height of the upstream portion of the filter media between the first end and the second end.

In another embodiment a floor cleaner is disclosed including a fluid flow path extending from a dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, a separator housing in the fluid flow path, and a cylindrical filter chamber. The separator housing includes a separator air inlet and a separator air outlet. The cylindrical filter chamber includes a first end, a second end, and a cylindrical sidewall extending between the first and second ends in a longitudinal direction. The cylindrical filter chamber further includes a cylindrical filter media in the fluid flow path downstream of the separator housing and upstream of the fluid flow motor. The cylindrical filter is spaced apart from the cylindrical sidewall by a gap. The length of the gap is less than 30% of a diameter of the cylindrical filter media. The filter chamber includes a filter inlet edge that extends into the filter chamber such that a radial distance between the filter media and the cylindrical sidewall is greater than a radial distance between the filter media and the filter inlet edge.

In another embodiment a floor cleaner is disclosed including a fluid flow path extending from a dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, a separator housing, and a cylindrical filter chamber. The separator housing includes a separator air inlet in communication with the dirty air inlet, a separator air outlet, an upper end, and a lower end. The separator housing further includes a debris collection chamber. A door is coupled to the lower end of the separator housing and is movable from a closed position to an open position to empty the debris collection chamber through the lower end of the housing. The cylindrical filet chamber includes a first end, a second end, and a cylindrical sidewall extending between the first and second ends. The cylindrical filter chamber further includes a cylindrical filter media in the fluid flow path downstream of the separator housing and upstream of the fluid flow motor. The cylindrical sidewall includes a filter inlet that enters the cylindrical sidewall tangentially, communicating the separator housing and the cylindrical filter chamber. The door on the lower end of the separator housing forms the first end of the filter chamber.

In another embodiment a floor cleaner is disclosed including a fluid flow path extending form a dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, a separator housing, and a cylindrical filter chamber housing an annular filter media. The separator housing includes a separator air inlet in communication with the dirty air inlet, and a separator air outlet. The cylindrical filter chamber includes an openable first end, a second end, and a cylindrical sidewall extending between the first and second ends. The second end has a filter chamber air outlet upstream of the fluid flow motor. The filter chamber has a filter inlet tangential to the cylindrical sidewall and in fluid communication with the separator air outlet. The annular filter media is positioned in the filter chamber. The filter media has an upstream portion spaced from the cylindrical sidewall between the first end and the second end, and a downstream portion forming a portion of the fluid flow path in communication with the chamber air outlet. The first end of the filter chamber is formed by a portion of the separator housing and the separator housing is separable from the filter chamber to open the first end of the filter chamber.

Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a floor cleaner according to one embodiment.

FIG. 2 is a partial cross-sectional view of the separator and dirt collection chamber of the floor cleaner of FIG. 1.

FIG. 3 is a cross-sectional view of the filter chamber with the filter media of the floor cleaner of FIG. 1.

FIG. 4 is a cross-sectional view of the filter chamber without the filter media of the floor cleaner of FIG. 1.

FIG. 5A is a sectional view through the floor cleaner showing the filter chamber of FIG. 4.

FIG. 5B is a detail view of the filter chamber inlet of FIG. 5A.

FIG. 6A is a view of the filter frame and the filter media removed from the floor cleaner.

FIG. 6B is an exploded view of FIG. 6A showing the filter media removed from the filter frame.

FIG. 6C is an alternate embodiment of the filter frame and filter media of FIG. 6A including a top portion covering the filter media.

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.

DETAILED DESCRIPTION

FIGS. 1 and 2 illustrate a floor cleaner 10. The floor cleaner 10 includes a fluid flow path from a dirty air inlet 42 to a clean air outlet 11, a fluid flow motor 12, a separator housing 14, and a cylindrical filter chamber 20 containing a filter frame 21 and a filter media 22. The separator housing 14 is positioned in the fluid flow path and includes an air treatment member 15 configured to separate debris from the air flow introduced from the dirty air inlet 42 and in the illustrated embodiment a dirt collection chamber 16 within the separator housing 14. Separated debris is collected in the dirt collecting chamber 16, and air exits the separator housing 14 via a clean air outlet 40 along the fluid flow path. The clean air outlet 40 is fluidly connected to a filter inlet 30 of the filter chamber 20 to further filter the air flow in the fluid flow path. Improvements in filtration efficiency increase floor cleaning performance and service life of the floor cleaner.

In the illustrated embodiment shown in FIG. 5, the filter chamber 20 includes a first end 26, a second end 28, and a cylindrical sidewall 24 extending between the first end 26 and the second end 28 in a longitudinal direction. In one embodiment, the filter frame 21 is removably positioned inside the filter chamber 20. In a use position, the filter frame 21 is arranged such that a top portion 31 of the filter frame is adjacent the first end 26 of the filter chamber and a bottom portion 33 of the filter frame is adjacent the second end 28 of the filter chamber. The filter frame 21 is configured to operably support the filter media 22 in the filter chamber 20 and includes an air passageway 55 downstream of the filter media 22 in communication with a filter chamber outlet 54. In the illustrated embodiment, the filter is cylindrical, and is disposed on the filter frame 21, surrounding or forming a hollow center portion that forms at least a portion of the air passageway 55. The annular filter media 22 forms a filter axis 80 along the air passageway 55. The filter frame 21 may include longitudinal ribs 23 extending between the top portion 31 and the bottom portion 33 providing structure and support around the air passageway. Air enters the filter chamber 20 through the filter inlet 30, which directs air generally tangentially to the cylindrical sidewall 24. Air passes through the filter media 22 filtering debris from the air flow before passing through the air passageway 55 and exiting the filter chamber outlet 54. The fluid flow path extends through the filter media 22 in a normal flow orientation (i.e., the fluid flow move radially inwards) toward the air passageway 55 at the center of the cylindrical filter.

In order to limit the amount of air flow bypassing the filter media 22 and directly entering the air passageway 55 or filter chamber outlet 54 without flowing through the filter media 22, an upper side 29 a and a lower side 29 b of the filter media 22 or filter frame 21 is positioned in sealing engagement with the filter chamber 20 and/or the separator housing 14 configured to direct air from the filter inlet 30 through the filter media 22. Stated another way, the filter media 22 is positioned in the filter chamber 20 configured to inhibit air from passing around the filter media during use.

In one embodiment, the lower side 29 b of the filter media 22 is in sealing engagement with the bottom portion 33 of the filter frame 21 and the bottom portion 33 of the filter frame 21 is in sealing engagement with the second end 28 of the filter chamber 20. In another embodiment, the lower side 29 b of the filter frame 21 is in sealing engagement with the second end 28 of the filter chamber 20 via a filter frame seal 35. The upper side 29 a of the filter and a top of the air passageway 55 are also closed or sealed in order to inhibit air bypassing the filter media 22 and directly entering the air passageway 55.

The upper side 29 a of the filter and the top of the air passageway 55 may be sealed by the same closure or by separate closures. In the illustrated embodiment, the top portion 31 of the filter frame closes the top of the air passageway 55 and a bottom side of the separator housing 14 seals the upper side 29 a of the filter media 22. In the illustrated embodiment, the separator housing 14 includes an openable door 18 on the bottom side of the separator housing 14, and the upper side 29 a of the filter media 22 is sealed by the openable door 18. When the separator housing 14 is removed, the filter media 22 is accessible for cleaning and service. In one embodiment shown in FIG. 6C, the filter frame includes a removable top portion 31′ extending over the filter media such that the filter frame seals the upper side 29 a of the filter media and closes the top of the air passage way 55 in a use position, configured such that the filter media 22 is accessible for cleaning when the top portion 31 is in a removed position. In another embodiment, the bottom side of the separator housing 14 provides a sealing surface to the upper side 29 a of the filter media and closes the air passageway 55. When the separator housing 14 is removed, the filter media 22 is accessible to the user and the air passageway 55 is opened.

The cylindrical filter chamber 20 and filter 22 are in the fluid flow path downstream from the separator housing 14 and upstream from the fluid flow motor 12. The cylindrical sidewall 24 of the filter chamber 20 extends between the first end 26 and the second end 28. The filter media 22 is positioned in the filter chamber 20, the filter media having an upstream portion 19 a and a downstream portion 19 b. The upstream portion 19 a is spaced from the cylindrical sidewall 24 between the first end 26 and the second end 28, and the downstream portion 19 b forms a portion of the fluid flow path upstream of the filter chamber outlet 54 and the fluid flow motor 12. In the illustrated embodiment, cylindrical filter media 22 is annular, wherein the upstream portion 19 a of the cylindrical filter includes the outer cylindrical surface 19 a of the filter media and the downstream portion 19 b includes the inner annular surface 19 b of the filter media 22.

When the air flow enters the tangential inlet 30 of the filter chamber 20, the air flows along the sidewall 24 and debris may settle from the airflow. In one embodiment, as shown in FIG. 3, the bottom portion 33 of the filter frame has a flange 27 that extends radially beyond the filter media 22 and, optionally, an upwardly directed circumferential wall 37 forming a debris collection area to receive the debris settling from the airflow or dropping from the surface of the filter media 22. The flange 27 and/or the circumferential wall 37 is disposed adjacent the sidewall 24 to collect settling debris. In one embodiment, shown in FIG. 4, the filter frame 21 includes a wiper or gasket 60 around the bottom portion 33, extending from the flange 27 or the circumferential wall 37 closing a gap between the filter frame 21 and the filter chamber 20. In one embodiment, the wiper 60 extends radially contacting the sidewall 24 configured such that when the filter frame 21 is removed from the filter chamber 20, the wiper 60 wipes the cylindrical sidewall 24 to remove excess dirt and debris from the filter chamber 20 and inhibit dirt and debris from entering the fluid flow motor 12. The wiper 60 can be molded from a flexible natural, thermoplastic, or thermoset elastomer material, such as, but not limited to, polymers of polypropylene, rubber, silicone, or polyurethane.

In the embodiment shown in FIG. 3, the filter media 22 is sealed in the filter chamber 20 at the upper side 29 a of the filter media and at the lower side 29 b. As discussed above, the bottom side of the separator housing 14 seals the upper side 29 a of the filter media. In the illustrated embodiment, the bottom side of the separator housing includes a downwardly extending protrusion 39 that encircles the upper side 29 a of the filter media in sealing engagement. The protrusion 39 also inhibits the filter media 22 from flexing or bowing and allowing air to bypass the media 22. In one embodiment, the protrusion 39 engages a top surface of the upper side 29 a of the filter media in sealing engagement. The top portion 31 of the filter frame 21 is configured to close the center air passageway 55. The lower side 29 b of the filter media is pressed against the filter frame 21 and the compression of the media 22 against the filter frame 21 provides a seal between the media and the frame. In the illustrated embodiment, the lower wall of the filter chamber 20 includes an upwardly extending protrusion 41 that encircles the lower side 29 b of the filter media in sealing engagement. The protrusion 41 also inhibits the filter media 22 from flexing or bowing and allowing air to bypass the media 22. In one embodiment, the protrusion 41 engages a bottom surface of the lower side 29 b of the filter media in sealing engagement. The filter frame 21 includes the seal 35 on the bottom portion 33 of the filter frame engaging the second end 28 of the filter chamber. In one embodiment, the top portion 31 includes a grip or handle portion 25 configured for the user to grasp to remove the filter frame 21 from the filter chamber 20, such as for cleaning or servicing of the assembly.

In the illustrated embodiment, the first end 26 of the filter chamber 20 is located under the separator housing 14 and the dirt collection chamber 16. In one embodiment, the dirt collection chamber 16 is separate from the separator housing 14, and the first end 26 of the filter chamber 20 is located under the dirt collection chamber 16. In the illustrated embodiment, the second end 28 of the filter chamber is located above the fluid flow motor 12 and includes the filter chamber outlet 54 fluidly communicating the downstream portion 19 b of the filter with the motor 12. The fluid flow motor 12 extends along a motor axis 82. As shown in FIG. 2 the fluid flow motor 12 is positioned such that the motor axis 82 is parallel to the filter axis 80. In one embodiment, the motor axis 82 extends along the filter axis 80. In one embodiment, the motor axis 82 and filter axis 80 are coaxial. In one embodiment, the motor is positioned such that the motor axis is transverse the filter axis.

The inlet 30 directs airflow into the filter chamber 20 generally tangentially to the cylindrical sidewall 24. The tangential inlet 30 fluidly communicates the separator housing 14 and the filter chamber 20. In particular, an airflow passage 61 extends between the clean air outlet 40 of the separator housing 14 to a filter inlet duct 62 forming the tangential inlet 30 of the filter chamber 20. The tangential inlet 30 is formed by an outlet aperture of the filter inlet duct 62 extending through the sidewall 24. The filter inlet duct 62 includes an inner wall 64 forming an inlet edge 66 of the filter inlet 30, an outer wall 68, a top wall 70 extending to and forming a top edge 50 of the filter inlet, and a bottom wall 72 forming a bottom 52 of the filter inlet. In the illustrated embodiment, the inner wall 64 extends into the filter chamber such that the radial dimension between the filter media 22 and the sidewall 24 is greater than the radial dimension between the filter media 22 and the inlet edge 66 of the filter inlet. The filter frame 21 and the filter chamber 20 include a mating notch and tab arrangement such that when the filter frame 21 is placed into the filter chamber 20, alignment of the notch and tab will properly orient the filter frame 21 within the filter chamber 20 to thereby align an opening 74 (FIG. 6A) in the circumferential wall 37 of the filter frame 2lwith the inlet duct 30 (FIG. 5A) of the filter chamber 20. As shown in FIG. 3, the filter inlet edge 66 extends approximately parallel to the filter media, or within about 10° of parallel.

In order to increase the efficiency and performance of the filtration system, a height of the tangential inlet aperture 30 is increased to be a substantial portion of a height of the filter media 22. This allows a steady stream of air to flow from the inlet 30 into the filter media 22. By increasing an inlet height H₁ such that it is a substantial portion of a filter media height H₂, the speed of air entering the filter chamber 20 and filter media 22 is reduced. The air speed is reduced because the increased inlet height H₁ provides a less restrictive air passageway. The reduced air speed entering the filter results in less air bypassing the filter media 22 to enter the air passageway 55 and more air flowing through the filter media 22. The increased air flow through the filter media 22 improves filtration performance. It has been found that when the inlet height is shorter relative to the filter media 22, the speed of the air entering the filter chamber 20 is greater because the inlet is more restrictive, tending to increase suction (decrease pressure) increasing the pressure difference between the inside of the system and the atmosphere, which may enable air to draw through weaker sealing connections bypassing the filter media 22, resulting in a decrease in filtration. When the air speed is greater, in certain configurations air is able to leak between the filter media and the sealing surfaces, such as the top portion 31 of the filter frame or the openable door 18 of the separator housing, to enter the air passageway 55 directly and bypass the filter media 22. Additionally, it has been found that when the height of the inlet H₁ is 50% or less than the height of the filter media exposed to air flow in use H₂, filtration performance is significantly reduced because the air speed is greater and there is less filter surface area exposed to the inlet for filtration. In the illustrated embodiment, the longitudinal height H₁ of the inlet 30 from the top edge 50 to the bottom 52 is a substantial portion of the longitudinal height of the cylindrical filter media 22 exposed to air flow in use H₂. In one embodiment, the longitudinal height H₁ is at least 60% of the longitudinal height H₂. In one embodiment, the longitudinal height H₁ is at least 75% of the longitudinal height H₂. In addition to decreased air speed entering the filter chamber 20, filtration is improved by a resulting increase in the surface area of the filter media 22 that is exposed to the inlet 30 air flow. This greater surface area allows more air flow through the filter media 22.

Additionally, the height of the tangential inlet H₁ is a substantial portion of a height of the filter chamber H₃ (FIG. 4). Similar to the height ratio of the inlet 30 relative to the filter media 22, the height ratio of the inlet 30 relative to the filter chamber 20 improves the performance of the filtration system. In one embodiment, the height of the filter chamber H₃ is the same as the height of the filter media exposed to air flow in use H₂. In another embodiment, the height of the filter media exposed to air flow in use H₂ is less than the height of the filter chamber H₃. In one embodiment, the height of the tangential inlet H₁ is at least 60% a height of the filter chamber H₃. In one embodiment, the height of the tangential inlet H₁ is at least 75% the height of the filter chamber H₃. In one embodiment, height H₂ of the filter media exposed to air flow in use is equal to the height of the filter chamber H₃.

In one embodiment, the filter chamber 20 is configured to provide a gap 56 between the filter 22 and the cylindrical sidewall 24 of the filter chamber to provide desired air flow around the filter 22. Desired filtration has been achieved with a gap 56 in the range of 5 millimeters to 20 millimeters. In one alternative, the gap 56 between the filter 22 and the adjacent sidewall 24 is between 5 millimeters and 10 millimeters. In another alternative, the gap 56 between the filter 22 and the adjacent sidewall 24 is larger than 5 millimeters to provide desired airflow around the filter 22.

In one embodiment, the gap 56 between the filter 22 and the cylindrical sidewall 24 of the filter chamber can be measured as a percentage of a cross-sectional diameter of the filter D₁. In one embodiment, the gap 56 is less than 30% of the cross-sectional diameter of the filter D₁. In an alternate embodiment, the gap 56 between the filter 22 and cylindrical sidewall 24 is less than 15% of the cross-sectional diameter of the filter D₁. In another embodiment the gap 56 is between 1% and 25% of the cross-sectional diameter of the filter D₁. The gap 56 allows air flow around the cylindrical filter 22. When the gap 56 is too small a percentage of the filter diameter D₁, air may tend to overcome the sealing surfaces, and bypass the filter 22. This results in air exiting through the filter chamber outlet 54 without being adequately filtered through the filter media 22. When the gap 56 is too large as a percentage of the filter diameter D₁, the speed of the air in the filter chamber 20 is more variable than desired. The air speed is lower near the sidewall 24 and higher near the filter 22, resulting in worse overall filtration. We have found desired filtration has been achieved with the gap 56 is in the range of 5% to 30% of the diameter of the filter D₁.

The gap 56 can also be measured as a ratio of the diameter of the filter D₁ relative to a diameter of the filter chamber D₂. In one embodiment, the ratio of the diameter of the filter D₁ to the diameter of the filter chamber D₂ is between 60% and 90%. In an alternate embodiment, the ratio of the filter diameter D₁ to the filter chamber diameter D₂ is between 75% and 90%. This ratio ensures substantial constant speed in the filter chamber and low pressure drop as air passes through, which provides high filtration efficiency.

In one embodiment, the cylindrical filter 22 includes a first cylindrical filter 22 a and a second cylindrical filter 22 b. The second cylindrical filter 22 b is nested within the first cylindrical filter 22 a. In one embodiment, the height of the first cylindrical filter 22 a is greater than the height of the second cylindrical filter 22 b. In a use position, the upper sides 29 a of the first and second cylindrical filters 22 a, 22 b are compressed and sealed as discussed above, such as by the top portion 31 of the filter frame or by the bottom door 18 of the dirt collection chamber. The filter 22 may be any desired filter media, including pleated or non-pleated, non-woven fiber, foam, high-efficiency particular air filter (HEPA), or other media. The first cylindrical filter 22 a and the second cylindrical filter 22 b may be made of the same material or different material.

In the illustrated embodiment, the tangential inlet 30 to the filter chamber 20 has a longitudinal height H₁ from the top edge 50 to the bottom edge 52 that is greater than the width from the inlet duct inner wall 64 to the outer wall 68 at the tangential inlet 30. In one embodiment, the height H₁ from the top edge 50 to the bottom edge 52 is at least twice the width of the inlet duct from the inner wall 64 to the outer wall 68. As a result of this ratio, the airflow path entering the filter media 22 from the separator housing 14 leaves the separator housing 14 with a lower pressure drop compared to arrangements where the width of the inlet is nearly equal to the height. This lower pressure drop produces adequate air flow for more efficient filtration.

Various features and advantages of the invention are set forth in the following claims. 

What is claimed is:
 1. A floor cleaner comprising: a fluid flow path extending from a dirty air inlet to a clean air outlet; a fluid flow motor positioned in the fluid flow path; a separator housing having a separator air inlet in communication with the dirty air inlet, and a separator air outlet; a cylindrical filter chamber having a first end, a second end, and a cylindrical sidewall extending between the first and second ends in a longitudinal direction, the filter chamber having a filter inlet tangential to the cylindrical sidewall in fluid communication with the separator air outlet; and a cylindrical filter media positioned in the filter chamber, the filter media having an upstream portion and a downstream portion, the upstream portion being spaced from the cylindrical sidewall, and the downstream portion forming a portion of the fluid flow path upstream of the fluid flow motor; wherein a longitudinal height of the filter inlet is at least 50% of a longitudinal height of the upstream portion of the filter media.
 2. The floor cleaner of claim 1 wherein the longitudinal height of the filter inlet is at least 60% the height of the longitudinal height of the filter media.
 3. The floor cleaner of claim 1 wherein a diameter of the cylindrical filter media is at least 60% of a diameter of the filter chamber.
 4. The floor cleaner of claim 1 wherein the filter inlet includes a filter inlet edge that extends into the filter chamber such that a radial distance between the filter media and the side wall is greater than a radial distance between the filter media and the filter inlet edge.
 5. The floor cleaner of claim 4 wherein the filter inlet edge extends approximately parallel to the filter media.
 6. The floor cleaner of claim 1 wherein the cylindrical filter chamber is positioned under the separator housing.
 7. The floor cleaner of claim 1 wherein a filter frame is positioned inside the filter chamber, wherein the filter frame is removable from the filter chamber.
 8. The floor cleaner of claim 7 wherein the cylindrical filter media is positioned on the filter frame, wherein the cylindrical filter media is removable from the filter frame.
 9. The floor cleaner of claim 7 wherein the filter frame includes a debris collection area adjacent the second end of the filter chamber.
 10. The floor cleaner of claim 7 wherein the filter frame includes a wiper that extends radially around the filter frame adjacent the second end of the filter chamber.
 11. The floor cleaner of claim 1 wherein the cylindrical filter includes a first cylindrical filter and a second cylindrical filter, the second cylindrical filter being nested within the first cylindrical filter.
 12. The floor cleaner of claim 11 wherein the separator housing includes a use position coupled to the floor cleaner and a removed position detached from the floor cleaner, wherein the longitudinal height of the first cylindrical filter is greater than the longitudinal height of the second cylindrical filter, and the first cylindrical filter is compressed by the separator housing in a use position.
 13. The floor cleaner of claim 1 wherein the longitudinal height of the filter inlet is as least twice the length of a width of the filter inlet in a lateral direction.
 14. The floor cleaner of claim 1 wherein a gap between the cylindrical filter media and the adjacent cylindrical sidewall is in the range of 5 to 10 millimeters.
 15. A floor cleaner comprising: a fluid flow path extending from a dirty air inlet to a clean air outlet; a fluid flow motor positioned in the fluid flow path; a separator housing in the fluid flow path, the separator housing having a separator air inlet and a separator air outlet; and a cylindrical filter chamber having a first end, a second end, and a cylindrical sidewall extending between the first and second ends in a longitudinal direction, the filter chamber having a cylindrical filter media in the fluid flow path downstream of the separator housing and upstream of the fluid flow motor, wherein the cylindrical filter media is spaced apart from the cylindrical sidewall by a gap, the length of the gap being less than 30% of a diameter of the cylindrical filter media; and wherein a filter inlet edge extends into the filter chamber such that a radial distance between the filter media and the cylindrical sidewall is greater than a radial distance between the filter media and the filter inlet edge.
 16. The floor cleaner of claim 15 wherein the length of the gap is less than 15% of the diameter of the cylindrical filter media.
 17. The floor cleaner of claim 15 wherein the gap is between 1 and 25% of the diameter of the cylindrical filter chamber.
 18. The floor cleaner of claim 15 wherein the cylindrical filter media has a diameter at least 70% of the diameter of the cylindrical filter chamber.
 19. The floor cleaner of claim 18 wherein the filter inlet edge extends approximately parallel to the filter media
 20. A floor cleaner comprising: a fluid flow path extending from a dirty air inlet to a clean air outlet; a fluid flow motor positioned in the fluid flow path; a separator housing having a separator air inlet in communication with the dirty air inlet, a separator air outlet, an upper end, and a lower end; a debris collection chamber located within the separator housing; a door coupled to the lower end of the separator housing and movable from a closed position to an open position to empty the debris collection chamber through the lower end of the separator housing; and a cylindrical filter chamber having a first end, a second end, and a cylindrical sidewall extending between the first and second ends, the cylindrical filter chamber including a cylindrical filter media in the fluid flow path downstream of the separator housing and upstream of the fluid flow motor, wherein the cylindrical sidewall includes a filter inlet that enters the cylindrical sidewall tangentially, communicating the separator housing and the cylindrical filter chamber, and wherein the door forms the first end of the filter chamber.
 21. The floor cleaner of claim 20 wherein the filter chamber is positioned below the lower end of the housing.
 22. The floor cleaner of claim 21 wherein the cylindrical sidewall extends between the first and second ends in a longitudinal direction, and wherein a longitudinal height of the filter inlet is at least 60% a longitudinal height from the first end to the second end of the cylindrical filter chamber.
 23. A floor cleaner comprising: a fluid flow path extending from a dirty air inlet to a clean air outlet; a fluid flow motor positioned in the fluid flow path; a separator housing having a separator air inlet in communication with the dirty air inlet, and a separator air outlet; a cylindrical filter chamber having an openable first end, a second end, and a cylindrical sidewall extending between the first and second ends, the second end having a chamber air outlet upstream of the fluid flow motor, the filter chamber having a filter inlet tangential to the cylindrical sidewall in fluid communication with the separator air outlet; and an annular filter media positioned in the filter chamber, the filter media having an upstream portion and a radially interior downstream portion, the upstream portion being spaced from the cylindrical sidewall, and the downstream portion forming a portion of the fluid flow path in communication with the chamber air outlet; wherein the filter chamber first end is formed by a portion of the separator housing and the separator housing is separable from the filter chamber to open the first end.
 24. The floor cleaner of claim 23 wherein the separator housing includes an upper end, a lower end, a debris collection chamber located within the separator housing, and a door coupled to the lower end of the separator housing and movable from a closed position to an open position to empty the debris collection chamber through the lower end of the housing, wherein the filter chamber first end is formed by the door. 